Abstract : A stimulated Raman scattering resonator is described which generates stimulated Raman scattering within an optical resonator and provides regeneration and unidirectional emission of radiation. A focusing mirror is provided for the pumping radiation and is combined with the stimulated Raman scattering resonator within a single optical structure. A semi-confocal type resonator having one totally reflecting plain mirror and one partially reflecting spherical mirror is employed to increase pumping irradiance.